Convert all css files to sass files by passing directory

convert_css_to_sass.sh

#!/bin/sh

cut="/usr/bin/cut"
sass_convert="/usr/bin/sass-convert"

if [ $# -ne 1 ];then
    echo "USAGE: convert_css_to_sass ~/target/directory"
    exit
fi
if [ -z "$1" ];then
    echo "USAGE: convert_css_to_sass ~/target/directory"
    exit
fi

first=`echo $1| $cut -c1`
case $first in
    /)
        #absolute path is passed
        target=$1
        ;;
    *)
        current=$(cd $(dirname $0); pwd)
        target=$(cd $current/$1; pwd)
        ;;
esac

if [ ! -d $target ]; then
    echo "$target doesn't seem to exist"
    exit
fi

filenames=$(find ${target} -type f -name *.css)

for file in ${filenames[@]};do
    filepath=${file%/*}
    filename=${file##*/}
    filename_noextension=${filename%.*}
    filename_extension=${filename##*.}
    $sass_convert -F css -T sass $file $filepath/$filename_noextension.sass
    done